Knives are one of humanity's most universal tools, and, as such, are used for numerous purposes: cutting foods or other inert objects, combat and self-defense, surgery, hunting, etc. Many knives, like the common chefs knife, have a fixed, non-moving blade, while most others, like the common folding knife and switchblade, have a moving (e.g., sliding or pivoting) blade. In the former case, the blade is always exposed with respect to the handle and must be housed in a sheath for safety or blade protection. In the latter case, the blade can be pivoted or retracted to lie housed within the confines of the handle.
Although fixed-blade knives are relatively easily deployed (e.g., by pulling the knife out of a sheath), their fixed blades render them relatively bulky, and, unless a locking sheath or the like is provided, relatively unsafe. Most folding knives are more compact and somewhat safer, since their blades can be withdrawn into their handles. However, with folding knives, it is typically necessary for a user to use two hands to deploy the knife, e.g., one to grasp the handle and one to pull open the blade. Further, even with “one handed” knives like the thumb-stud folding knife, it is still necessary to remove the knife from whatever it is being carried in, and to properly grip the handle, prior to use. In situations where quick blade deployment is critical, such as combat, skydiving, scuba diving, rock climbing, and self-defense, any such delay can be critical.
Attempting to solve these problems, various “quick-deployment” folding knives have been provided over the years. For example, U.S. Pat. No. 5,349,753 to Gaffney (“Gaffney”) discloses a “one-handed” knife comprising a knife portion and a separable tether. Pulling down on the knife portion causes the blade to swing open, via a sliding bar and cam mechanism, while pulling down further on the knife portion causes the separable tether to disengage, releasing the knife portion from the separable tether for use. For a sliding knife, the blade is actuated via a sliding rack-and-gear mechanism. While these designs allow for the knife to be quickly deployed, the actuation mechanisms are not particularly robust, and it is difficult to lock the blades in an open position. Additionally, separable tethers can oftentimes become disengaged unintentionally, or they can be too difficult to disengage. Further, the weight of the knife itself may cause the blade to inadvertently partially or fully deploy when the knife is dangled at the end of the separable tether, and the direction of blade deployment does not lend itself to quick use or safety. More specifically, to deploy the folding knife in Gaffney, one would have to carefully grasp the handle so that the path of the blade is not obstructed. With the sliding knife in Gaffney, to leave the blade in its most useful position (e.g., in a cutting position with the blade extending away from the thumb and forefinger, as opposed to an overhand stabbing position, with the blade extending down from the pinky), one would have to either grasp the knife handle in an underhanded fashion, or turn the knife over subsequent to deployment.
Another “one-handed” knife is shown in U.S. Pat. No. 5,878,500 to Emerson (“Emerson”). There, a folding knife is provided with a special sheath. The back of the knife blade has a hook, and the inside of the sheath is provided with a complementary lip. As the knife is pulled out of the sheath, the hook on the blade encounters the lip on the inside of sheath, which causes the blade to swing open as the knife is extracted. While this design facilitates quick blade deployment, it is still necessary to reach into the sheath to grasp the knife. Additionally, the lip and hook may become misaligned when the knife is withdrawn from the sheath, in which case the blade will not automatically deploy.
Accordingly, it is a primary object of the present invention to provide a sliding knife whose blade can be actuated with one hand.
Another primary object of the present invention is to provide a sliding knife that can be worn on (or attached to) the body, and that can be simultaneously detached from the body and deployed, with one hand.
Another object of the present invention is to provide a “one-handed” sliding knife that has both a robust blade deployment mechanism and a robust, secure blade locking system.